Capacity

What it is

Capacity is an AI app builder for people who have never written code. The home page says "Capacity was made for people who have never written a line of code," and its headline promise is "Turn your idea into a real app. No code. No developers. No getting stuck." It builds web applications, and its distinguishing choice is what the company calls a spec-first method: it asks you questions and writes down what the app should do before it builds anything. The pages do not say where the company is based.

What you build and how

You start by describing the idea "like you'd explain it to a friend." The home page says there are "no technical terms, no tutorials." You can type into a prompt box on the site, or use Capacity from inside Claude or ChatGPT. The site's sample chat has a user asking Claude for "a booking app for my yoga studio," with Capacity tools named create_app, apply_changes and screenshot running behind it, and the result live on a capacity.studio address.

The step that sets it apart comes next. Under the heading "It asks before it builds," the site says "instead of guessing what you meant, Capacity asks a few smart questions first: what it's for, who will use it, how it should feel. Then it builds exactly what you agreed on." A comparison page on the same site explains the reasoning: instead of "hoping the AI understands your vague description," you define specifications, and the company argues this reduces the misinterpretation and constant corrections it associates with prompt-based tools. Its feature list for the product includes project brief management, user story tracking, UX specifications, design system specs, an AI advisor it calls a co-founder, iterative spec updates and living documentation. The same page says your database schema, relationships and security rules are planned as part of the specification "not just generated on-the-fly from a prompt."

What comes out is described as "a real app, not a demo." The home page says it can have "member accounts, logins, saved information, payments: everything real products have." The comparison page gives a longer example: a SaaS dashboard with user authentication, subscription management, an admin dashboard and analytics. The site's menus also point to an AI landing page builder, an AI MVP builder, a custom web app service, a React boilerplate generator and a wedding website builder, as well as an AI mobile app builder entry.

On the technical side the comparison page says Capacity generates code with React, Next.js, TypeScript and Tailwind CSS for the frontend, and uses Supabase for the backend, which it lists as providing PostgreSQL, authentication, real-time subscriptions and edge functions. It says Capacity "currently focuses on web applications built with React and Next.js," and that apps are fully responsive. The home page says apps work on phones, tablets and computers, and that clean, modern design comes standard. You can steer the look in words: "warm and friendly" or "serious and premium," and "it matches it."

Changing the app is conversational too. When something breaks you say so in plain words, such as "the button doesn't work" or "this page looks off," and, in the site's words, "your AI co-founder finds the problem and fixes it for you," explaining what happened in normal language at any hour. The home page says each change is built and previewed right away, then published on your domain, and that the same app can be opened in Capacity later with its version history intact.

Publishing is a single step: "one click puts it on the internet with a link you can share." Capacity handles hosting, database, domain and versions. The comparison page says custom domains are supported for every deployed app, with SSL certificates provisioned and managed automatically, and that Capacity integrates with GitHub.

There are two ways to pay for the building. You can build from Claude or ChatGPT, where "your subscription writes the code, Capacity runs it," so every message runs on your own AI plan and not on Capacity credits. Or you can use the built-in Capacity agent, which spends credits when you build or change things.

What the pages say about plans and ownership

The pricing statement is short: "Plans start at $25/month." The home page adds that building from Claude or ChatGPT "is unlimited on every paid plan" because it runs on your own AI subscription, while the built-in agent uses credits that "never expire." It says the first app is free ("Your first app is free"), and a comparison page says Capacity offers a free tier and that no credit card is needed to start. The pages give no credit counts, no names for the paid plans and no limits on apps or users, and the site keeps a separate Pricing page.

On ownership the claims are strong. The home page answers "Is the app really mine?" with "Yes, 100%. Your app, your data, your members: all yours," and says that if you leave "you can take everything with you, including the code a developer would need. No lock-in." The comparison page repeats that you own your code, that Capacity generates standard React and Next.js you can deploy anywhere, and that specifications and code are yours to keep. It says nothing about SOC 2, HIPAA or other compliance certifications, and it names no hosting region.

Support is described as an AI co-founder available "day and night," and the site links a Discord community, a changelog, a roadmap, a support page and an affiliate program.

Who it suits and who it does not

Capacity suits a non-technical founder who has an app idea, such as a booking tool for a studio or a small SaaS dashboard, and wants it live without hiring a developer. The question-first flow helps most when you have not yet thought through roles, data and screens, because the questions force those decisions early and write them into the spec. It also suits anyone who already pays for Claude or ChatGPT and prefers to spend that subscription on building instead of buying separate credits. An agency or a freelancer could use the exported code as a handoff, since the company says the code is standard and yours.

It is a web-app builder. The company says it currently focuses on web applications, so a team that needs a native iOS or Android release should confirm what Capacity offers before committing. The backend is Supabase, so apps assume PostgreSQL and its authentication model rather than a database of your own choosing. People who want to work in code directly, or who need a published compliance statement before storing customer data, will find the pages silent on both points. The spec-first approach also adds a round of questions before anything appears, which is a trade against tools that show a first draft from a single prompt.